Pigs and Genetic Resources
The commercial pig-producing sector is currently dominated by a handful of breeds, all of which originate from European or North American animals bred in the eighteenth century. The market supplied by breeding organizations has been extensively consolidated, and there are few international suppliers of breeding animals.
To maximize the performance of animals for fattening, hybrid breeding programmes are established in countries with intensive pig production. Consumer preferences for lean pork, as in the western world, and the requirements of growing urban populations have led to a narrow spectrum of acceptable carcass quality that must be achieved if pig farmers are to participate in the global pork marketing chain. As a result the current commercial system depends on this limited range of genetic variety.
On the other hand, small-scale producers rely mainly on local breeds adapted to particular conditions and feed resources whose hardiness makes them ideal for low-input production systems. Because most of the genetic diversity in domestic pigs (Sus scrofa domestica) is found in local breeds, the loss of genetic resources has been dramatic in the past 50 years as pig production has intensified. Attempts to introduce breeds used in commercial pig production to small-scale producer settings have often failed because the necessary inputs have been unavailable.
With the new challenges to global agriculture arising from climate change and decreasing availability of natural resources, the need to preserve genetic diversity is crucial. The pig sector will have to adapt to increasing global temperatures and weather extremes and the consequent changes in feed availability and to emerging pathogens.
Enhancing pigs’ genetic diversity with valuable traits other than the currently pursued high fertility and daily weight gain will allow breeding programmes to address the various emerging challenges.